The invention relates to a method for operating a plant for producing tablets.
A plant for producing tablets typically contains a so-called rotary press. The main component of the rotary press is a rotor that accommodates a set of lower and upper punches. The punches work together with dies in a die plate of the rotor, wherein a stationary filling device sequentially fills holes in the die before the added material can be compressed with the assistance of the press punches. When the general term “rotor” is used in the following and above, it also includes the “rotor package” i.e., the parts belonging to the rotor that form the unit which can be installed and removed with the rotor. This includes for example the cam carriers for the cams that control the punches while the rotor is rotating.
A computer system is used to control the operation and monitoring of such a rotary press. To this end, the rotary press contains a series of signal generators that emit signals on the condition, arrangement and function of components and assemblies of the press, the signals being processed in the computer system. For example, the pressure rollers are assigned pressure measuring devices that determine the maximum pressure and its progress. Overall, the computer system contains operating and control software for controlling and monitoring the operation of the rotary press. The relevant details will not be further addressed, however. The communication between the rotary press and computer system normally occurs by means of a wired signal connection such as a cable. It is however also possible to transmit data free of contact or wirelessly.
For a press, DE 199 33 817 A1 discloses assigning the upper and lower tool a memory that can be read with the assistance of a reading head. For example, the operating life of the punch tools can be monitored with the assistance of such an arrangement. DE 199 20 377 A1 discloses a communication system of actuators and sensors in the tablet machine as well as a control computer. Communication occurs by means of a bus system.
DE 102 07 764 B4 discloses providing a plurality of components and/or assemblies of the rotary press with a transponder, and saving at least one identification number in the transponders that identifies the components and/or assembly. A component and/or assembly plan is saved in the computer system. After the tabletting machine is assembled, the transponders are read with a reading head connected to the computer system. The read-out data are compared in the computer system with the component and/or assembly plan. In this manner, it is possible to automatically monitor a rotary press during assembly.
The rotors or rotor package in rotary presses are normally removed as a unit, for example to clean the press. In addition, different rotors can be used in a rotary press. Types of production are accordingly distinguished, for example depending on whether monolayer, two-layer or three-layer tablets are to be produced. The operation and control of the rotary press differs depending on the type of production. When installing a different rotor package, it has been normal up to now to make manual entries on the operating terminal of the computer system by means of which the operating and control software is adapted to the type of rotor.
However, it takes time to manually enter information on the respective rotor type. In addition, incorrect entries can be made which can cause the tablet press to become damaged or malfunction. An important piece of information for identifying a rotor type is the station number that indicates the number of dies or die holes and punch pairs. If the station number is incorrectly entered, the bad tablets are not sorted out. Bad tablets become part of the good product, and a complete batch may have to be discarded which of course not only takes additional time but also causes a loss of material.
The object of the invention is therefore to present a system for producing tablets in which the operating and control software in a computer system is automatically adapted to the different rotor packages.